PCB Assembly


PCBA in our life

Did you know that all the electronic devices you use in your daily life have a common basic building block ?Almost any electronic device, including your PC, laptop, smart phone, game console, microwave oven, TV, dishwasher, etc., will not work properly without PCB Assembly. So, what is PCB Assembly?

What does PCB Assembly mean?

PCB assembly refers to the process of soldering and assembling electronic components on prefabricated parts, matting and manufacturing printed circuit boards (PCBs). The mass production will use professional production machinery. PCBA means the printed circuit board assembly process.


The difference between PCB and PCBA


PCB is

refers to an empty circuit board. In this state, the circuit board does not contain any electronic components and looks like a green slate with dividing lines and spaces. Therefore, the PCB cannot work, unless and until the entire assembly.



On the other hand, we also call the PCBA is the process of assembling components on the PCB. In electronic equipment, we use assembled PCBA instead of PCB products.

What is a circuit board assembly(PCB Assembly)


Circuit board components participate in various steps.  The expected results and the use of PCBA are one of the main considerations that determine the components and general circuit board assembly process.


Components of PCBA

The following are some parts and components PCB assemblies:

  1. Basic printed circuit board or substrate
  2. The electronic components that will be mounted on the circuit board. This depends on the use of the circuit board and the complexity of the equipment. For example, PCBA for radios is relatively simpler than PCBA for computers. In fact, some computers can have up to 12 different circuit layers on the PCB.
  3. Soldering materials, solder wire, solder paste, preforms and other welding materials. The preform depends on the type of welding.
  4. Flux
  5. Other welding equipment such as soldering station, wave soldering machine, inspection, test equipment and SMT equipment. The use of equipment depends on the expected results, cost and time resources. For example, the reflow soldering process used in electronics is mainly gas phase and infrared. Based on the above factors, choose one of the processes.


When we prepared all the necessary components, the assembly process can begin. But before we get into the assembly process (it is a different type), let us know more about the circuit board itself.

Three main types of printed circuit boards


Epoxy and other composite materials make up the circuit board. The PCB is for physically support the components and electrically connect them to form a real-time circuit.


In the simplest sense, a PCB will consist of a thin layer of insulating material and a layer of copper foil, laminated to the underlying substrate (usually made of epoxy, fiberglass or similar composite materials). The number of layers on the PCB depends on the use and application. The lines or circuit traces on the PCB are created with the help of chemical etching. These lines help current flow and connect various components together.


There are different types of circuit boards or PCBs.

According to the type of application, the manufacturer will choose the PCB. The most widely PCB types as  following:

layer PCBs are not as common as multilayer boards. Use both sides of a board

Multi-layer PCBs are usually mass-produced, economical and compact, with up to 10 or 12 layers

Rigid PCB Stronger substrate, high impact applications, military, aerospace

Flexible PCB mobile parts application, higher cost and longer life

Metal core PCB metal plate, copper, speclialist applications, such as conductive or thermal



Method of mounting circuit board components


The technology used to assemble the circuit board and its various components is called the mounting technology board assembly in the circuit. Depending on the application, cost, scale and other considerations, manufacturers use different kinds of installation methods.


Surface mount components


SMT part

One method is surface mount components (Surface mount components, also known as SMT), which is to directly connect the electronic components standing on the PCB. This technology was originally called “flat mounting”.

DIP part

Most of the electronic boards currently produced are manufactured using SMT. Because of its increased circuit density and ability to produce results on smaller circuit boards, it has replaced the more traditional through-hole technology (more on the next point).

Board through hole components


Another technology is through-hole technology. The electronic components are inserted through the holes built into the circuit board and then soldered to the pads. Welding can be done manually or using a plug-in installation machine.


Through hole technology replaces the traditional point-to-point structure. As double-sided and multi-layer boards become more and more popular, through holes are becoming popular. DIP components will connect the components and the conductive layer, to ensure the normal operation of the circuit board.  These components is for equip with leads to connect to the other side of the through-hole board.


Electromechanical pcb assembly


Electro-Mechanical components use electrical and mechanical units to cover a wide range of functions such as generating electricity, controlling switches and other mechanical tasks.


Therefore, it can usually be time-time consuming. However, major manufacturers like RayPCB like us, use this technology and break down the process into individual market segments and use experts in each segment. Therefore, we can shorten the lead time.


Common uses of each type of PCB Assembly


We use the surface mount technology is most commonly. We most widely use the SMT technologies in the electronics field.  And most of  electronic products will use SMT techonolgy. Such as smart phones, computers, TVs, microwave ovens, etc. But before SMT technology, the through-hole technology that dominated the personal computer market.


In fact, IBM was the pioneer of this process and pushed it to the mainstream. Currently, through-hole technology is more used for larger components, such as electrolytic capacitors and semiconductors, because it can hold components better than SMT.




PCB is a very close part of our contemporary life, although we still haven’t noticed it. Over the past few decades, the technology for effectively assembling and installing components has rapidly developed into a quick-to-point structure from through-hole to SMT. In addition, each has its own advantages and disadvantages, making them very suitable for certain tasks rather than others.